﻿
using System;
using System.Web;
using System.Web.Mvc;

namespace good1.Web.Controllers.Filters
{

    public class CacheFilterAttribute : ActionFilterAttribute
    {
        private const int Second = 1;
        private const int Minute = 60 * Second;
        private const int Hour = 60 * Minute;
        public const int SecondsInDay = Hour * 24;


        /// <summary>
        /// Gets or sets the cache duration in seconds. The default is 10 seconds.
        /// </summary>
        /// <value>The cache duration in seconds.</value>
        public int Duration
        {
            get;
            set;
        }

        public int DurationInDays
        {
            get { return Duration / SecondsInDay; }
            set { Duration = value * SecondsInDay; }
        }

        public CacheFilterAttribute()
        {
            Duration = 10;
        }

        public override void OnActionExecuted(ActionExecutedContext filterContext)
        {
            if (Duration <= 0) return;

            HttpCachePolicyBase cache = filterContext.HttpContext.Response.Cache;
            TimeSpan cacheDuration = TimeSpan.FromSeconds(Duration);

            cache.SetCacheability(HttpCacheability.Public);
            cache.SetExpires(DateTime.Now.Add(cacheDuration));
            cache.SetMaxAge(cacheDuration);
            cache.AppendCacheExtension("must-revalidate, proxy-revalidate");
        }
    }
}
